Automatic step-by-step stock feeder



April 14, 1953 CHUY AUTOMATIC STEP-BY-STEP STOCK FEEDER 2 SHEETSSHEET 1 Filed Jan. 5, 1951 III [46 0! Attorney .2 SHEETSSHEET 2 A Home w rat-AK I 1% April 14, 1953 N. cHUY AUTOMATIC STEP-BY-STEP STOCK FEEDER Filed Jan. 5, 1951 Patented Apr. 14, 1953 7 2,634,974 AUTOMATIC STEP-BY-STEP STOCK FEEDER Nicholas Chuy, Detroit, Mich., assignor to Ruth Goldie Horowitz, Detroit, Mich.

Application January 5, 1951, Serial No. 204,569

7 Claims.

This invention relates to a stock feeder adapted to be employed as an attachment for use with automatic material working machines such as punch presses, for cutting and stamping machines.

More particularly, an aim of the present invention is to provide a fluid pressure operated feeding attachment adapted to be connected to and coordinated with an automatic material working machine intermittently feeding stock thereto in a coordinated relationship to the operation of the machine.

Another object of the invention is to provide a fluid pressure operated feeding device capable of being readily adjusted for feeding stock in a step-by-step movement and wherein the length of each feeding step may be readily varied as desired.

Another object of the invention is to provide a feeding apparatus wherein a fluid pressure is employed to initially operate clampingmeans for gripping the stock and for thereafter operating a feeding unit, by which the clamping means is carried, for advancing stock through the feeding apparatus.

A further object of the invention is to provide a novel valve structure forming a part of the feeding apparatus and which is actuated by a part of the material working machine for intermittently opening the valve to admit the fluid medium to the feeding apparatus to accomplish the intermittent or step-by-step feeding.

Various other objects and advantages of the invention will hereinafter become more fully apparent from the following description of the drawings, illustrating a presently preferred em-' bodiment thereof, and wherein:

Figure 1 is an end elevational view showing an automatic material working machine'with the stock feeding attachment applied thereto;

Figure 2 is an enlarged top plan view partly in horizontal section of the stock feeding apparatus;

Figure 3 is a cross sectional view thereof taken substantially along a plane as indicated by the line ,33 of Figure 4;

Figure 4 is a horizontal sectional view taken substantially along a plane as indicated by the line 44 of Figure 3;

Figure 5 is a cross sectional view similar to Figure 3 but showing the stock gripping elements in engaged positions;

Figure 6 is an enlarged vertical sectional view of the novel valve unit of the stock feeder, and

Figure '7 is an end elevational view partly in section looking from right to left of Figures 2 and 4, showing the feeder employed for feeding strip stock.

Referring more specifically to the drawings, for the purpose of illustrating a preferred application and use of the automatic stock feeder, designated generally [0 and comprising the invention, a conventional automatic material working machine is shown at H in Figure 1, as for example, a punchpress. The machine H includes an upwardly facing shelf or supporting surface I2 on which a part of the stock feeder is supported and is provided with a large belt pulley [3 for driving a shaft [4 of the machine i l which is disposed at the same end of the machine as the end thereof on which the stock feeder I0 is disposed. The belt pulley I3 is driven in a direction as indicated by the arrow [5 in Figure l by an endless belt l6 which is trained over a belt pulley IT on the drive shaft of a motor l8 which is supported on a shelf bracket IQ of the machine H. The parts II to l9, inclusive, constitute no part of the present invention but have merely been illustrated and briefly described to aiford a better understanding of the stock feeder i0 and the manner in which it is connected to and operated in unison with the machine I l The stock feeder l0 includes an elongated cylinder 20 having a forward end which is closed by a cylinder head 2| and. a rear end which is closed by a cylinder head 22. The cylinder heads 2| and 22 are secured to the ends of the cylinder 2!] by suitable fastenings such as bolts 23 which extend loosely through openings in the heads and threadedly engage tapped recesses 24 in the ends of the cylinder 20. The head 21 is provided with an external enlargement 25 and has a bore 26 extending centrally through said head and through the enlargement 25, as best seen in Figure 4. The head 22 is provided with a centrally disposed bore 21 which aligns with the bore 26 each of which bores is axially disposed relatively to the cylinder 20. The head 22 is provided with an externally disposed stufiing box 28 which aligns with the bore 27. As best seen in Figures 3, 5 and '7, a base 29 is formed integral with a portion of the cylinder 20 and extends to adjacent the ends thereof and is provided with openings 30 adapted to receive fastenings, not shown, by which the base may be secured on the shelf l2.

A piston 3| is slidably mounted in the cylinder 20 and has hollow shafts or rods formed integral with the opposite ends thereof and which project therefrom. One of said rods 32 extends from the forward side of the piston 3! reciprocally through the bore 25. The other shaft or rod 33 extends from the rear end of the piston 3! reciprocally through the bore 2'5 and stuffing box 26. The rods -32 and 33 are disposed in alignment and have aligned bores 34. The piston 3! has a bore extending axially therethrough which aligns with and forms a part of the shaft bores so that said bore extends between and opens outwardly of the remote ends of the hollow shafts or rods 32 and 33. The rod or shaft 32 is provided with opposed longitudinally extending grooves 35 which slidably engage the restricted inner terminals of a pair of setscrews iii which are threaded radially into the boss 25 through radial bores 38 which open into the bore 26 and outwardly of the periphery of the boss 25. Each of the bores 38 has an inner threaded end to threadedly receive a setscrew and an enlarged outer end through which the setscrew is loosely inserted or removed. The terminals 36 by engaging the slots 35 prevent the piston 55% from turning in the cylinder for a purpose which will hereinafter become apparent. An expansion coiled spring 259 is disposed around the shaft 32 between the head 2! and the adjacent end of the piston 3! for urging the piston toward the head 22 and for normally retaining it in abutting engagement therewith, as illustrated in Figure 4, wherein the piston 3! and shafts 32 and 53 are shown in fully retracted position. Adjacent the head 2!, the cylinder 253 is provided with a vent port fill to exhaust the air from the cylinder space between the head and piston 35 or to admit air to said space to allow the piston 35 to slide in the cylinder to unhampered by a vacuum or air pressure between the piston and cylinder head 2 I.

As best illustrated in Figures 3, d and 5, the piston 3i, which constitutes the master piston of the apparatus ii] is provided with radially disposed, diametrically opposed recesses of circular cross section forming radial cylinders d! having restricted openings 3-2 at their inner ends which open radially into the bore 34. As best seen in Figure 2, the piston t! is provided with oppositely disposed milled-out flat surfaces 43 into which the remote endsof the cylindrical chambers t! open and which terminate at their forward ends contiguous with the forwardmost portions of the chambers ii. The fiat surfaces A3 extend to the rear end of the piston 3!. Said piston 35 is provided with a central boss 44 which normally abuts against the cylinder head 22 so that the annular end surface 45 at the rear end of the piston 3!, surrounding said boss 44 is spaced from the cylinder head 22, for a purpose which will hereinafter become apparent. The flat surfaces it extend to the annular end surface 45 and in combination with the cylinder 28 form communicating passages between the end 45 of the piston 3! and the cylindrical chambers 4|.

The openings 2 are of noncircular cross section preferably being enlarged or elongated in directions longitudinally of the cylinder 20. Each of said openings 42 slidably receives therein a gripping dog as which is supported thereby for radial reciprocating movement relatively to the master piston 3!. Each dog 16 has an enlarged head at its outer end forming a piston 41. The pistons i? slidably engage the cylindrical chambers 4! and are each urged radially outwardly thereof by an expansion coiled spring 48 disposed around each of the gripping dogs it between its piston 47 and the bed of its cylindrical chamber 4!.

Spaced bushings 49 are detachably secured in the bore 34 by setscrews 50. One of the setscrews 50 is threaded radially into the inner threaded end of a radial bore 5! of the piston 3! which bore has an unthreaded outer end which opens into one of the milled-out or recessed surfaces it. The other setscrew 5!] is threaded radially into the shaft 32 adjacent its forward end and is countersunk therein so as not to interfere with sliding movement of the shaft through the bore 26. Accordingly, one bushing 49 is disposed in the piston 3! and the other bushing 49 is disposed in the forward end of the shaft 32. The bushings 49 are shown as having a bore of circular cross section for receiving a strand of stock 52 of circular cross section such as a wire or rod to be fed to the machine I! by the stock feeder ii! and the bores of the bushings 59 are sized to slidably guide the stock 52 in step-by-step movement through the feeder ill. The inner ends of the gripping dogs 46 are provided with grooves of arcuate cross section as seen at 53 which extend longitudinally of the inner face of the dogs in which the stock 52 is partially received to be effectively gripped when the dogs 46 are in projected, gripping positions, as illustrated in Figure 5. By substituting bushings, not shown, having bores of noncircular cross section, strip stock 52a of noncircular cross section may be fed through the feeder i0 and effectively gripped by the dogs 36, as illustrated in Figure 7.

The cylinder 20 is provided with a pair of diametrically aligned threaded openings at adjacent the rear cylinder head 22, each of which extends radially through the cylinder wall. A nipple 55 is threaded into each opening 54. The inner ends of the bores of the nipples 55 open into the cylinder 23 and said nipples are disposed in alignment with the cylindrical recesses l! of the master piston 3! when said master piston is in a fully retracted position against the rear cylinder head 22, as seen in Figure i. Each nipple 55 is connected at its opposite outer end to an end of a short pipe or hose 56. A stud 57 is threaded into an upwardly opening recess 58 in the top of the cylinder 20 between the threaded openings 54. The stud 5'! is provided with a head 59 forming an inverted T-shaped coupling the aligned open ends of which are connected to the opposite ends of the pipes or hoses 56, as best illustrated in Figure 3. As seen in Figure 1, a hose at has one end connected to the other, upwardly extending end of the coupling 5S. The opposite end of the hose til is connected to the bottom of a housing 6! of a valve, designated generally 62 and opens into an enlarged bottom chamber 63 of said housing iii. The chamber 63 forms an enlarged bottom portion of a bore or recess 64 of the housing 8! the opposite end of which opens outwardly of the upper end of said housing 6! An elongated hollow valve body 55 has a lower portion which is externally sized and shaped to snugly fit in and slidably engage the bore 6,4. The valve body 65 is closed at its lower end and is provided with an internally threaded open upper end 66 which is normally closed by a threaded plug 6'! having a rounded substantially hemispherical head 88 which projects upwardly from the valve body 65. The hollow interior chamber 69 of the valve body 65 isclosed at its] lower end butisprovidedwlth a radial port which opens outwardly of the valve body adjacent its closed bottom. The body portion 65 is provided with a longitudinally extending groove 1| in which is slidably received the valve body 65in its dotted line position of Figure 6 is disposed so that its radial port 'lll opens intothe enlarged chamber 63. The valve body 65 is provided with an-externally enlarged upper end forming an annular downwardly facing shoulder 13 again'st which one end of an expansion coiled spring "seats. The spring 14 is disposed around the valve body 65 and has its opposite end bearin against the, upper end of the housing 6| for'urging the valve body 65up- 'wardly to its full line position ofFigure 6. The "housing 6| is provided with a radial port in the wall thereof, as seen at 15, which opens to the atmosphere and which communicates with the bore 64 above the chamber 63 and below the valve body 65, when the latter is in its raised, full line position of Figure 6.

- An air hose 16 having one end, not shown, adapted to be connected to a source of air under pressure has a nipple 11 at its opposite outlet end which is threaded radially through the externally thickened upper portion of the valve body 65 and which opens into the chamber 69 beneath and adjacent the plug 61. The housing 6| is provided with a bracket 18 through which extend fastenings 19 for securing the bracket 78 to an end wall of the machine II for mounting the valve 62 thereon beneath and slightly outwardly of the belt pulley l3. A cam 80 is secured to the outer face of the belt pulley l3 and has an outer inclined edge disposed to strike the head 68 at each revolution of the belt pulley I3. The front cylinder head 2| has a threaded opening 8| extendin therethrough to adjustably receive an elongated threaded rod 82 which extends therethrough and which has an inner end adjustably disposed in the cylinder 26 and which maybe adjusted longitudinally thereof. The inner-end of the rod 82 forms an adjustable stop for limiting the movement of the master piston 3| from right to left of Figures 2 and 4 or toward the forward head 2|.

Assuming that the stock feeder I0 is applied as illustrated in the drawings to the machine H and has the stock strand 52 extending through its bore 34, as the belt pulley |3 makes each clockwise rotation the cam 80 will engage the head 68 to displace the valve body 65 downwardly to its dotted line position of Figure 6 to thus uncover the port 10 so that the compressed air in the chamber 69, supplied thereto through the hose 16 may escape through the enlarged chamber 63 into the hose 60 thence through the coupling 59, pipe or hose 56 and nipple 55 into the.

cylinder 20. The valve body 65 in its lowermost dotted line position of Figure 6 will seal the exhaust port to prevent escape of the compressed air therethrough to the atmosphere. The compressed air entering the cylinder 20 through the nipple 55 is initially ejected against the heads 41 and the gripping dogs 46 to force said parts radially inwardly of one another against the action of the springs 48 from their positions of Figure 3 to their positions of Figure 5 so that the grooved portions 53 will grip the stock 52. Thereafter, the air will escape from the cylindrical recesses 4| through the spaces between the recessed surfaces 43 of the piston 3| and the wall of the cylinder 20 into the space between the rear cylinder head 22 and the annular end portion 45 of the piston 3|. The air impinging against the piston surface 45 will force the piston 3| to move from right to left of the cylinder 20 from its position of Figure 4 to its position of Figure 2 against the action of the coiled spring 39. As the stock 52 is gripped by the dogs 46 during this movement of the master piston 3|, the stock will be advanced from right to left of Figures 2 and 4 a distance equal to the travel of the piston 3|, which distance is regulated by adjustment of the adjustable stop 82. This operation will occur while the cam is in engagement with the head 68 to hold the valve body 65 in its depressed dotted line position of Figure 6. After the stock 52 has been advanced it will be engaged by a part of the machine ll, not shown, by which the operation to be performed on the stock is accomplished and while the stock 52 after advancement is thus engaged, the cam 86 will ride out of engagement with the head 68 thus permitting the spring '14 to displace the valve body 65 upwardly to its full line position of Figure 6. When this occurs the exhaust port 15 will be uncovered by the valve 55 allowing the air to escape therethrough to the atmosphere thus releasing the air pressure in the cylinder 26 between the cylinder head 22 and piston 3|. When this occurs and while the stock 52 is still held by the partof the machine H the springs 42 will force the gripping dogs 46 radially outwardly of the piston 3| from their positions of Figure 5 to their positions of Figure 3 since the air pressure against the piston-like heads 4'! of the gripping dogs will thus have been released. Immediately thereafter the spring 39 will expand and in so doing will cause the piston 3| to slide from left to right from its position of Figure 2 back to its position of Figure 4. The feeder I6 will then be ready to repeat the operation just previously described so that the stock 52 or 52a may thus be fed to the machine H by an intermittent or step-by-step motion. The hollow shafts 32 and 33 slide through the bores 26 and 21, respectively, during this movement of the master piston 3| and the stems 36 engaging the grooves 35 prevent the piston from turning in the cylinder 26 so that the piston-like heads 41 are always disposed to directly receive the force of each charge of compressed air admitted to the cylinder through the nipples 55 and when the piston 3| is in its retracted position of Figure 4.

Various modifications and changes are contemplated and may obviously be resorted to, without departing from the spirit or scope of the invention as hereinafter defined by the appended claims.

'I claim as my invention:

1. An automatic stock feeding device for use with automatic material processing machines comprising a cylinder having a forward cylinder head at one end thereof and a rear cylinder head at its opposite rear end, a master piston reciprocably disposed in said cylinder, a shaft projecting from each end of the master piston, said shafts being axially disposed relatively to the cylinder, said cylinder heads having aligned bores through which the shafts reciprocably extend; a bore extending longitudinally through said shafts and piston forming a stock passage through which an elongated strand or strip of stock is adapted to be fed from the rear end of the cylinder to and through the forward end thereof, said piston having diametrically opposed outwardly opening cylindrical recesses each provided with a restricted inner end opening radially into the piston bore, a gripping dog reciprocably disposed in the restricted end of each cylindrical recess, each of said gripping dogs having a piston-like head reciprocably disposed in its associated cylindrical recess, an expansion spring disposed in the cylinder between the forward cylinder head and piston forurging the piston toward the rear cylinder head, abutment means on the master piston normally engaging the rear cylinder head and spacing the adjacent end of the piston therefrom, said master piston having recessed portions extending from its rear end and opening into said cylindrical recesses forming passages between the cylindrical recesses and the space between the rear end of the master piston and the rear cylinder head, a conduit for a fluid medium under pressure having dual discharge ends connected to said cylinder and discharging diametrically in the cylinder in alignment with one another and with said cylindrical recesses of the master piston when said master piston is in engagement with the rear cylinder head for intermittently supplying a fluid medium under pressure to the cylinder whereby said dogs will be initially projected inwardly into gripping engagement with the stock and the piston thereafter displaced toward the forward cylinder head to advance the stock therethrough, said gripping dogs being released from gripping engagement with the stock and said piston being returned to a position in engagement with the rear cylinder head by the expansion spring when the pressure of the fluid medium is released from the cylinder.

2. A stock feeder as in claim 1, and expansion coiled springs seated in said cylindrical recesses and bearing against said piston-like heads for normally retaining the gripping dogs in retracted disengaged positions.

3. A stock feeder as in claim 1, and means for slidably keying the master piston and shafts to the cylinder to prevent rotation of the piston relatively to the cylinder whereby said cylindrical recesses will be disposed in alignment with and between the discharge ends of said fluid pressure conduit when the master piston is in en gagement with the rear cylinder head.

4. A stock feeder as in claim 1, and guide bushings detachably secured in the bore of the master piston and shafts, said guide bushings having bores shaped to slidably accommodate the 6 stock for maintaining a portion of the stock in a position to be engaged by the gripping dogs.

5. A stock feeder as in claim 1, said gripping dogs each having an elongated gripping face extending longitudinally of the piston and shaft bore, said gripping faces being recessed to accommodate and engage a substantial portion of the stock when the gripping dogs are in projected, gripping positions.

6. A stock feeder for use with automatic material processing machines comprising a shaft, a piston interposed thereon intermediate of the ends of said shaft, said shaft having a bore extending longitudinally therethrough and through the piston adapted to form a passage for stock in strand or strip form, a cylinder in which said piston is reciprocably disposed, a forward cylinder head fixed to one end of said cylinder and a rear cylinder head fixed to the opposite end of said cylinder, said cylinder heads having aligned bores through which the ends of the shaft reciprocably extend, spring means interposed between the forward cylinder head and piston for normally retaining the piston in a retracted position in engagement with the rear cylinder head, a supply conduit for a fluid medium under pressure having dual outlets discharging radially into said cylinder, said piston having radially extending recesses aligning with said dual outlets when the piston is in engagement with the rear cylinder head, gripping dogs reciprocably disposed in said radial recesses and extending into the piston and shaft bore and adapted to engage and grip the stock when the gripping dogs are projected inwardly by a fluid medium under pressure admitted to the cylinder through said dual outlets, said piston being displaced toward the forward cylinder head by the fluid medium under pressure impinging against portions of the piston, and springs urging each of said gripping dogs to .a released position for disengaging the gripping dogs. from the stock when the pressure of the fluid medium in the cylinder is released, said spring means thereafter returning the piston to a position in engagement with the rear cylinder head for positioning the gripping dogs in alignment with said dual outlets.

7. A stock feeder as in claim 6 and an adjustable stop extending into the cylinder through the forward cylinder head for limiting the travel of the piston toward the forward cylinder head to regulate the distance that the stock can be fed intermittently by each movement of the piston toward the forward cylinder head.

NICHOLAS CHUY,

References Cited in the file of this patent UNITED STATES PATENTS Number 

